2002

6.6

2001

7.2

2004

7.4

2007

5.8

2006

6.1

2007

6.7

2007

6.9

2002

6.2

2008

7.6

1979

7.3

1985

8.3

1980

8.1

2007

7.4

1977

10.0

2006

6.6

1998

6.8

1936

8.3

1943

5.4

1961

0.0

1964

5.0